Funding for this research was provided by:
Received: 2 November 2018
Accepted: 25 March 2019
First Online: 18 April 2019
Ethics approval and consent to participate
: The Regional Committee for Medical Research in Western Norway approved the study. All individuals gave their informed consent to participate prior to the inclusion in the study.
: Not applicable.
: The authors declare that they have no competing interests.
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